Download or read book Cold Fusion Production and Decay of Neutron Deficient Isotopes of Dubnium and Development of Extraction Systems for Group V Elements written by and published by . This book was released on 2008 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excitation functions for the 1n and 2n exit channels of the 208Pb(51V,xn)259-xDb reaction were measured. A maximum cross section of the 1n exit channel of 2070$+1100\atop{-760}$ pb was measured at an excitation energy of 16.0 ± 1.8 MeV. For the 2n exit channel, a maximum cross section of 1660$+450\atop{-370}$ pb was measured at 22.0 ± 1.8 MeV excitation energy. The 1n excitation function for the 209Bi(50Ti,n)258Db reaction was remeasured, resulting in a cross section of 5480$+1730\atop{-1370}$ pb at an excitation energy of 16.0 ± 1.6 MeV. Differences in cross section maxima are discussed in terms of the fusion probability below the barrier. The extraction of niobium (Nb) and tantalum (Ta) from hydrochloric acid and mixed hydrochloric acid/lithium chloride media by bis(2-ethylhexyl) hydrogen phosphate (HDEHP) and bis(2-ethylhexyl) hydrogen phosphite (BEHP) was studied. The goal of the experiments was to find a system that demonstrates selectivity among the members of group five of the Periodic Table and is also suitable for the study of dubnium (Db, Z = 105). Experiments with niobium and tantalum were performed with carrier (10-6 M), carrier free (10-10 M) and trace (10-16 M) concentrations of metal using hydrochloric acid solution with concentrations ranging from 1 - 11 M. The extraction of niobium and tantalum from mixed hydrochloric acid/lithium chloride media by HDEHP and BEHP as a function of hydrogen ion (H+) concentration was also investigated. The data obtained are used as the basis to discuss the speciation of niobium and tantalum under the conditions studied and to evaluate possible extraction mechanisms. The 74Se(18O,p3n)88gNb excitation function was measured to determine the best energy for producing the 88Nb used in chemistry experiments. A maximum cross section of 495 +- 5 mb was observed at an 18O energy of 74.0 MeV. The half life of 88gNb was measured and determined to be 14.56 ± 0.11 min.
Download or read book Cold Fusion Production and Decay of Neutron deficient Isotopes of Dubnium and Development of Extraction Systems for Group V Elements written by Jacklyn Marie Gates and published by . This book was released on 2008 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Production and Decay Properties of Neutron Deficient Isotopes with N written by Julio Antonio Heredia Cardona and published by . This book was released on 2012 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Production and Decay Properties of Neutron Deficient Isotopes with N written by and published by . This book was released on 2012 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Decay Studies of Neutron deficient Isotopes of Astatine Polonium and Bismuth written by Janis Bueling Dairiki and published by . This book was released on 1971 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Studies of Neutron deficient Isotopes of Emanation Francium and Radium thesis written by Floyd Franklin Momyer and published by . This book was released on 1953 with total page 76 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Characterization of Group V Dubnium Homologs on DGA Extraction Chromatography Resin from Nitric and Hydrofluoric Acid Matrices written by and published by . This book was released on 2012 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Studies of the chemical properties of superheavy elements (SHE) pose interesting challenges due to their short half-lives and low production rates. Chemical systems must have extremely fast kinetics, fast enough kinetics to be able to examine the chemical properties of interest before the SHE decays to another nuclide. To achieve chemistry on such time scales, the chemical system must also be easily automated. Most importantly however, a chemical system must be developed which provides suitable separation and kinetics before an on-line study of a SHE can be performed. Relativistic effects make studying the chemical properties of SHEs interesting due to the impact these effects could have on the SHEs chemical properties. Relativistic effects arise when the velocity of the s orbital electrons approach the speed of light. As this velocity increases, the Bohr radius of the inner electron orbitals decreases and there is an increase in the particles mass. This contraction results in a destabilization of the energy of the outer d and f electron orbitals (5f and 6d in the case of SHE), which can cause these to expand due to their increased shielding from the nuclear charge. Another relativistic effect is the spin-orbit splitting for p, d, and f orbitals into j = 1 ± 1/2 states. This can lead most interestingly to a possible increased stability of element 114, which due to large spin-orbit splitting of the 7p orbital and the relativistically stabilized 7p12 and 7s orbital gives rise to a closed shell ground state of 7s27p122. The homologs of element 105, dubnium (Db), Ta and Nb and the pseudo-homolog Pa, are well known to hydrolyze and form both neutral and non-neutral monoatomic and polyatomic species that may cause issues with extraction from a given chemical system. Early ion-exchange and solvent-extraction studies show mixed results for the behavior of Db. Some studies show Db behaving most similar to Ta, while others show it behaving somewhere between Nb and Pa. Much more recent studies have examined the properties of Db from HNO3/HF matrices, and suggest Db forms complexes similar to those of Pa. Very little experimental work into the behavior of element 114 has been performed. Thermochromatography experiments of three atoms of element 114 indicate that the element 114 is at least as volatile as Hg, At, and element 112. Lead was shown to deposit on gold at temperatures about 1000 C higher than the atoms of element 114. Results indicate a substantially increased stability of element 114. No liquid phase studies of element 114 or its homologs (Pb, Sn, Ge) or pseudo-homologs (Hg, Cd) have been performed. Theoretical predictions indicate that element 114 is should have a much more stable +2 oxidation state and neutral state than Pb, which would result in element 114 being less reactive and less metallic than Pb. The relativistic effects on the 7p12 electrons are predicted to cause a diagonal relationship to be introduced into the periodic table. Therefore, 114{sup 2+} is expected to behave as if it were somewhere between Hg{sup 2+}, Cd{sup 2+}, and Pb{sup 2+}. In this work two commercially available extraction chromatography resins are evaluated, one for the separation of Db homologs and pseudo?homologs from each other as well as from potential interfering elements such as Group IV Rf homologs and actinides, and the other for separation of element 114 homologs. One resin, Eichrom's DGA resin, contains a N, N, N', N'-tetra-n-octyldiglycolamide extractant, which separates analytes based on both size and charge characteristics of the solvated metal species, coated on an inert support. The DGA resin was examined for Db chemical systems, and shows a high degree of selectivity for tri-, tetra-, and hexavalent metal ions in multiple acid matrices with fast kinetics. The other resin, Eichrom's Pb resin, contains a di-t-butylcyclohexano 18-crown-6 extractant with isodecanol solvent, which separates analytes based on steric interactions between the cavity of the crown ether and electrostatic interactions between the oxygen's of the ether and cations in the mobile phase. This particular resin has been shown to have an extremely high uptake affinity for Pb, a direct homolog of element 114, and is thus a good initial extractant to examine for a potential element 114 chemical system. Figure 1.1 shows the respective extractant molecules from the DGA and Pb resins. Batch uptake experiments were conducted to examine the uptake behavior of Ta on the DGA resin. Batch uptake experiments were also conducted to examine the uptake behavior of Ge on the Pb resin. Column experiments were designed based on batch uptake experiments of Ta, Am, Pa, Np, Zr, and Nb to establish a sequential extraction of Group IV/V homologs as well as Am for potential use as a Db chemical system.
Download or read book Decay Properties of Neutron Deficient Isotopes in the Xenon Barium Massregion written by John M. D'Auria and published by . This book was released on 1967 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Extraction Chromatography written by and published by Elsevier. This book was released on 1975-06-01 with total page 585 pages. Available in PDF, EPUB and Kindle. Book excerpt: Extraction Chromatography
Download or read book Handbook of Nuclear Chemistry written by Attila Vértes and published by Springer Science & Business Media. This book was released on 2003 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt: Impressive in its overall size and scope, this five-volume reference work provides researchers with the tools to push them into the forefront of the latest research. The Handbook covers all of the chemical aspects of nuclear science starting from the physical basics and including such diverse areas as the chemistry of transactinides and exotic atoms as well as radioactive waste management and radiopharmaceutical chemistry relevant to nuclear medicine. The nuclear methods of the investigation of chemical structure also receive ample space and attention. The international team of authors consists of 77 world-renowned experts - nuclear chemists, radiopharmaceutical chemists and physicists - from Austria, Belgium, Germany, Great Britain, Hungary, Holland, Japan, Russia, Sweden, Switzerland and the United States. The Handbook is an invaluable reference for nuclear scientists, biologists, chemists, physicists, physicians practicing nuclear medicine, graduate students and teachers - virtually all who are involved in the chemical and radiopharmaceutical aspects of nuclear science. The Handbook also provides for further reading through its rich selection of references.
Download or read book Mendeleev to Oganesson written by Eric R. Scerri and published by Oxford University Press. This book was released on 2018 with total page 323 pages. Available in PDF, EPUB and Kindle. Book excerpt: An edited volume featuring chapters on multidisciplinary aspects of the Periodic Table, particularly focusing on the history and philosophy of chemistry
Download or read book The Disappearing Spoon written by Sam Kean and published by Little, Brown. This book was released on 2010-07-12 with total page 333 pages. Available in PDF, EPUB and Kindle. Book excerpt: From New York Times bestselling author Sam Kean comes incredible stories of science, history, finance, mythology, the arts, medicine, and more, as told by the Periodic Table. Why did Gandhi hate iodine (I, 53)? How did radium (Ra, 88) nearly ruin Marie Curie's reputation? And why is gallium (Ga, 31) the go-to element for laboratory pranksters? The Periodic Table is a crowning scientific achievement, but it's also a treasure trove of adventure, betrayal, and obsession. These fascinating tales follow every element on the table as they play out their parts in human history, and in the lives of the (frequently) mad scientists who discovered them. The Disappearing Spoon masterfully fuses science with the classic lore of invention, investigation, and discovery -- from the Big Bang through the end of time. Though solid at room temperature, gallium is a moldable metal that melts at 84 degrees Fahrenheit. A classic science prank is to mold gallium spoons, serve them with tea, and watch guests recoil as their utensils disappear.
Download or read book The Chemistry of Superheavy Elements written by Matthias Schädel and published by Springer Science & Business Media. This book was released on 2003-04-30 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the first to treat the chemistry of superheavy elements, including important related nuclear aspects, as a self contained topic. It is written for those – students and novices -- who begin to work and those who are working in this fascinating and challenging field of the heaviest and superheavy elements, for their lecturers, their advisers and for the practicing scientists in the field – chemists and physicists - as the most complete source of reference about our today's knowledge of the chemistry of transactinides and superheavy elements. However, besides a number of very detailed discussions for the experts this book shall also provide interesting and easy to read material for teachers who are interested in this subject, for those chemists and physicists who are not experts in the field and for our interested fellow scientists in adjacent fields. Special emphasis is laid on an extensive coverage of the original literature in the reference part of each of the eight chapters to facilitate further and deeper studies of specific aspects. The index for each chapter should provide help to easily find a desired topic and to use this book as a convenient source to get fast access to a desired topic. Superheavy elements – chemical elements which are much heavier than those which we know of from our daily life – are a persistent dream in human minds and the kernel of science fiction literature for about a century.
Download or read book Introduction to Radiation Protection written by Claus Grupen and published by Springer Science & Business Media. This book was released on 2010-04-20 with total page 429 pages. Available in PDF, EPUB and Kindle. Book excerpt: This account of sources of ionizing radiation and methods of radiation protection describes units of radiation protection, measurement techniques, biological effects, environmental radiation and many applications. Each chapter contains problems with solutions.
Download or read book The Periodic Table written by Paul Parsons and published by Quercus. This book was released on 2014-03-11 with total page 353 pages. Available in PDF, EPUB and Kindle. Book excerpt: As one of the most recognizable images in science, the periodic table is ingrained in our culture. First drawn up in 1869 by Dmitri Mendeleev, its 118 elements make up not only everything on our planet but also everything in the entire universe. The Periodic Table looks at the fascinating story and surprising uses of each of those elements, whether solid, liquid or gas. From the little-known uses of gold in medicine to the development of the hydrogen bomb, each entry is accompanied by technical data (category, atomic number, weight, boiling point) presented in easy-to-read headers, and a colour coding system that helps the reader to navigate through the different groups of elements. A remarkable display of thought-provoking science and beautiful photography, this guide will allow the reader to discover the world afresh.
Download or read book Radioactivity Radionuclides Radiation written by Joseph Magill and published by Springer Science & Business Media. This book was released on 2004-10-14 with total page 276 pages. Available in PDF, EPUB and Kindle. Book excerpt: Offers basic data on more than 3,600 radionuclides. Emphasizes practical application such as basic research, acheo0logy and dating, medical radiology and industrial. Balanced and informative details on the biological effects of radiation and resultant controversy. Trimmed down student version of a product that costs many times the price.
Download or read book The Effects of Relativity in Atoms Molecules and the Solid State written by Stephen Wilson and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 341 pages. Available in PDF, EPUB and Kindle. Book excerpt: Recent years have seen a growing interest in the effects of relativity in atoms, molecules and solids. On the one hand, this can be seen as result of the growing awareness of the importance of relativity in describing the properties of heavy atoms and systems containing them. This has been fueled by the inadequacy of physical models which either neglect relativity or which treat it as a small perturbation. On the other hand, it is dependent upon the technological developments which have resulted in computers powerful enough to make calculations on heavy atoms and on systems containing heavy atoms meaningful. Vector processing and, more recently, parallel processing techniques are playing an increasingly vital role in rendering the algorithms which arise in relativistic studies tractable. This has been exemplified in atomic structure theory, where the dominant role of the central nuclear charge simplifies the problem enough to permit some prediction to be made with high precision, especially for the highly ionized atoms of importance in plasma physics and in laser confinement studies. Today's sophisticated physical models of the atom derived from quantum electrodynamics would be intractable without recourse to modern computational machinery. Relativistic atomic structure calculations have a history dating from the early attempts of Swirles in the mid 1930's but continue to provide one of the primary test beds of modern theoretical physics.
